Role of advection in atmospheric ammonia; A Case study at a Japanese lake basin influenced by agricultural ammonia sources

Kubota, Tomohiro; Kuroda, Hisao*; Watanabe, Mirai*; Takahashi, Akiko*; Nakazato, Ryoji*; Tarui, Mika*; Matsumoto, Shunichi*; Nakagawa, Keita*; Numata, Yasuko*; Ouchi, Takao*; et al.

Atmospheric Environment, 243, p.117856_1 - 117856_9, 2020/12

https://doi.org/10.1016/j.atmosenv.2020.117856

The dry and wet depositions of atmospheric ammonia (NH) is one of the important pathways of nitrogen loads to aquatic ecosystems. Crop and livestock agriculture, one of the largest emitters of NH in Asian countries, are known to cause high spatial and seasonal variation of NH and influence the surrounding lake basin areas via its dry and wet deposition. However, the spatial characteristics of the NH concentration in basin scale are not completely understood for regulation in NH emission. Here we aim to clarify dominant factors of spatial and seasonal variations of the NH concentration in a eutrophic lake basin surrounded by agricultural areas in Japan. Passive sampling over various land use categories in the basin was conducted at 36 sites in total from October 2018 to January 2020. Interestingly, the observed NH concentration near the livestock houses were higher in winter than summer, which was inconsistent with knowledge of seasonal changes of current NH emission inventory based on temperature-driven volatilization process. Comparing monthly NH concentrations with various meteorological factors, we suggested the importance of seasonal advection of NH from high emission sources to which has been rarely paid attention by the previous past studies. As for this, should be considered for lake ecosystem management since deposition of NH is known to be closely related to the ecological processes such as phytoplankton blooming.

A Model intercomparison of atmospheric Cs concentrations from the Fukushima Daiichi Nuclear Power Plant accident, phase III; Simulation with an identical source term and meteorological field at 1-km resolution

Sato, Yosuke*; Sekiyama, Tsuyoshi*; Fang, S.*; Kajino, Mizuo*; Qurel, A.*; Qulo, D.*; Kondo, Hiroaki*; Terada, Hiroaki; Kadowaki, Masanao; Takigawa, Masayuki*; et al.

Atmospheric Environment; X (Internet), 7, p.100086_1 - 100086_12, 2020/10

https://doi.org/10.1016/j.aeaoa.2020.100086

The third model intercomparison project for investigating the atmospheric behavior of Cs emitted during the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident (FDNPP-MIP) was conducted. A finer horizontal grid spacing (1 km) was used than in the previous FDNPP-MIP. Nine of the models used in the previous FDNPP-MIP were also used, and all models used identical source terms and meteorological fields. Our analyses indicated that most of the observed high atmospheric Cs concentrations were well simulated, and the good performance of some models improved the performance of the multi-model ensemble. The analyses also confirmed that the use of a finer grid resolution resulted in the meteorological field near FDNPP being better reproduced. The good representation of the wind field resulted in the reasonable simulation of the narrow distribution of high deposition amount to the northwest of FDNPP and the reduction of the overestimation over the area to the south of FDNPP. In contrast, the performance of the models in simulating plumes observed over the Nakadori area, the northern part of Gunma, and the Tokyo metropolitan area was slightly worse.

Impacts of anthropogenic source from the nuclear fuel reprocessing plants on global atmospheric iodine-129 cycle; A Model analysis

Kadowaki, Masanao; Katata, Genki*; Terada, Hiroaki; Suzuki, Takashi; Hasegawa, Hidenao*; Akata, Naofumi*; Kakiuchi, Hideki*

Atmospheric Environment, 184, p.278 - 291, 2018/07

AA2017-0580.pdf:2.03MB

https://doi.org/10.1016/j.atmosenv.2018.04.044

The long-lived radioactive iodine (I) is a useful geochemical tracer in the atmospheric environment. We recently observed clear seasonal trends in air concentration and deposition of I in Japan. Using these data, we developed a global atmospheric I transport model to reveal key processes for the global atmospheric I cycle. The model generally reproduced the observed seasonal change in air concentration and deposition of I in Japan, and the global distribution of I concentration in rain as presented in past literature. Numerical experiments changing the intensity of anthropogenic and natural sources were conducted to quantify the impact of anthropogenic sources on the global I cycle. The results indicated that the atmospheric I from the anthropogenic sources was deposited in winter and can be accumulated mainly in the northern part of Eurasia. In contrast, the atmospheric I from the natural sources dominated the deposition in summer. These results suggested that the re-emission process of I from the Earth's surface may be important as a secondary impact of I in the global-scaled environment. Furthermore, although wet deposition dominated the total deposition in the Northern hemisphere, dry deposition regionally and seasonally contributed to the total deposition over arctic and northern part of Eurasia in winter, suggesting that the dry deposition may play a key role in the seasonal change of I deposition in the Northern hemisphere high latitudes.

Aerosol deposition and behavior on leaves in cool-temperate deciduous forests, 3; Estimation of fog deposition onto cool-temperate deciduous forest by the inferential method

Katata, Genki; Yamaguchi, Takashi*; Sato, Haruna*; Watanabe, Yoko*; Noguchi, Izumi*; Hara, Hiroshi*; Nagai, Haruyasu

Asian Journal of Atmospheric Environment, 7(1), p.17 - 24, 2013/03

https://doi.org/10.5572/ajae.2013.7.1.017

Fog deposition onto the cool-temperate deciduous forest in northern Japan was estimated by the inferential method using the parameterizations of deposition velocity and liquid water content of fog (LWC). Two parameterizations of fog deposition velocity derived from the field experiments and numerical simulations were tested. The empirical function between horizontal visibility (VIS) and LWC was applied to produce hourly LWC as input data of the inferential method. Weekly mean LWC computed from VIS had a good correlation with the one sampled by an active string-fog collector. Fog deposition calculated by the inferential method agreed with that computed from thorough fall data within the factors of 2 to 3. The results indicated that the inferential method using the current parameterizations of deposition velocity and LWC can provide a rough estimation of water input due to fog deposition onto cool-temperature deciduous forests.

Aerosol deposition and behavior on leaves in cool-temperate deciduous forests, 1; A Preliminary study of the effect of fog deposition on behavior of particles deposited on the leaf surfaces by microscopic observation and leaf-washing technique

Watanabe, Yoko*; Yamaguchi, Takashi*; Katata, Genki; Noguchi, Izumi*

Asian Journal of Atmospheric Environment, 7(1), p.1 - 7, 2013/03

https://doi.org/10.5572/ajae.2013.7.1.001

SEM-EDX analysis was performed using birch leaves collected from urban area and suburb area in northern Japan. Collected leaves were divided into three treatments: (1) untreated, (2) wash leaf surface (adaxial side) with deionized water, and (3) wipe leaf surface with Kimwipes. In untreated samples, many various-shaped particles including soil particles and organic debris were deposited on the surface. Sulfur (S) particles were observed on the surface of samples collected from urban area. After treatments of (2), soil particles and S particles were washed off by water, although coarse particles still remained on the leaf surface. Although treatment of (3) removed almost all particles from surface, NaCl particles were found in both urban area and suburb area. Our study revealed that the behavior of particles depends on environmental conditions such as rain.

Experimental verification for real-time environmental emergency response system; WSPEEDI by European tracer experiment

Furuno, Akiko; Terada, Hiroaki; Chino, Masamichi; Yamazawa, Hiromi*

Atmospheric Environment, 38(40), p.6989 - 6998, 2004/12

https://doi.org/10.1016/j.atmosenv.2004.02.074

We have been developing the computer-based emergency response system WSPEEDI which predicts long-range atmospheric dispersion of radionuclides discharged into the atmosphere due to a nuclear accident. The first version of WSPEEDI has a shortage that the spatial and temporal variation of the atmospheric boundary layer was very simply parameterized. Therefore we have developed the new version accomplished with the atmospheric dynamic model, in which the turbulent diffusivity in the mixing layer is calculated with a turbulence closure model. This paper describes the results of performance evaluation of the new version of WSPEEDI by comparing the simulation results with the European Tracer Experiment data. As a result of the verification, it was shown that the increase in the horizontal resolution largely improved the accuracy of the model prediction. The use of the turbulence closure model instead of the simple parameterization largely contributed to improve reproducibility of horizontal distribution of plumes.

Evaluation of a long-range lagrangian dispersion model with ETEX

Yamazawa, Hiromi; Furuno, Akiko; Chino, Masamichi

Atmospheric Environment, 32(24), p.4343 - 4349, 1998/00

https://doi.org/10.1016/S1352-2310(98)00188-5

no abstracts in English